Remote fieldwork and museum collections reveal hidden pit viper diversity in High Asia 

Published in ZooKeys, a recent study revises the Himalayan pit viper group using a combination of fresh and historical DNA, morphology, skeletal anatomy, and ecological observations.

The high mountain ranges of Asia remain among the least biologically explored regions of the continent. Now, an international team of researchers has shown that one of their most elusive venomous snakes, long treated a single species, is in fact a complex of five distinct species, three of which are new to science.

Published in the open-access journal ZooKeys, the study revises the Himalayan pit viper group using a combination of fresh and historical DNA, morphology, skeletal anatomy, and ecological observations. The data reveals that what scientists had long treated as a single widespread species, the Himalayan pit viper first described in 1864, actually consists of multiple deeply distinct evolutionary lineages.

The analyses identified five clearly distinct species-level lineages, i.e. the Himalayan pit viper in the strict sense, Gloydius chambensis described in 2022, and three previously unrecognised species from different parts of Pakistan and Nepal. Alongside genetic divergence, these lineages exhibit distinct morphological and skeletal variations.

Phylogeny and distribution of five pit viper species in the Himalaya and Hindu Kush. Image credit: Dr Daniel Jablonski

“These mountain systems still harbour overlooked vertebrate diversity and hold important clues to the biogeography of Asia,” says Daniel Jablonski of Comenius University Bratislava, who has been conducting extensive research in Pakistan and Afghanistan for many years.

“By combining modern field sampling with data from historical museum specimens, we uncovered evolutionary lineages that had remained hidden for more than a century after the original description of the Himalayan pit viper.”

Daniel Jablonski

A key element of the discovery was the integration of newly collected material with a powerful source of evidence: DNA extracted from museum specimens collected in the 19th and early 20th centuries. This included the original type specimen of the Himalayan pit viper, allowing the researchers to clarify the identity of the species in its strict scientific sense.

The study underscores the enduring scientific value of natural history collections. Indeed, specimens gathered by earlier generations of explorers and preserved in museums are still helping scientists solve modern biological puzzles, especially in regions where fieldwork remains difficult.

In fact, part of the discovery had been waiting in plain sight. “Museum specimens are not just records of the past. They are active research tools and essential infrastructure for future science,” says Sylvia Hofmann from the Museum Koenig as part of the Leibniz Institute for the Analysis of Biodiversity Change, who has comprehensively worked in the Himalaya and Tibetan Plateau during the past 20 years.

“Some of the key evidence had been sitting in museum collections for more than a hundred years. We just didn’t have the tools to recognise it. As analytical methods continue to improve, the scientific value of these collections will only grow and revealing biodiversity we didn’t even know was there.”

Sylvia Hofmann

Representatives of the herpetofauna play an important role in the ecosystem, particularly as ecological indicators, within the food chain, and as predators in pest control. A group of top predators in the region consist of pit vipers adapted to mountainous environments, which have so far been studied only very inadequately in the Himalayan region.

“Our work aims to close these gaps in knowledge and to lay the groundwork and provide inspiration for further, in-depth studies on this ecologically and medically relevant group.”

Frank Tillack of the Museum für Naturkunde Berlin, Leibniz Institute for Evolution and Biodiversity Research

Tillack maintains close ties with Nepalese colleagues and has been collaborating with them for 35 years on projects concerning the biodiversity of herpetofauna in the Himalaya.

An important part of the study is the osteology of these snakes, including the skull anatomy of the lectotype BMNH 1946.1.19.64 of Gloydius himalayanus, collected more than 160 years ago.
Image credit: Kristin Mahlow-Tillack.

The study also emphasises how much remains to be discovered in regions that have long been difficult to access for scientific research. “Pakistan’s high mountains are still full of biological surprises,” says Rafaqat Masroor of the Pakistan Museum of Natural History, the country’s leading herpetologists.

“This finding highlights how little we still know about a region long shaped by socio-political instability.”

Rafaqat Masroor

Beyond taxonomy, the findings also carry an important conservation message:

“Each of the newly recognised species seems to occupy a relatively restricted range in fragile mountain environments, highlighting new ecological and evolutionary questions.”

Daniel Jablonski

Without recognising such diversity, it would be impossible to assess it accurately or protect it effectively.

Original study:

Jablonski D, Tillack F, Mahlow-Tillack K, Petzold A, Wilzo M, Das A, Idrees M, Baniya CB, Masroor R, Hofmann S (2026) Integrative taxonomy reveals previously undescribed diversity within the Gloydius himalayanus complex (Squamata, Viperidae, Crotalinae) from the Himalaya and Hindu Kush. ZooKeys 1280: 83-153. https://doi.org/10.3897/zookeys.1280.182768

A Philosopher’s Serpent: New Grass-Green Pitviper Discovered in China’s Giant Panda National Park

The species name honours the philosopher known as Laozi, whose teachings emphasise the balance between humanity and the natural world.

The misty forests of the Giant Panda National Park in western Sichuan have long been a focus for biodiversity conservation. While the park is synonymous with its namesake bear, recent research has highlighted a different kind of resident. A team of scientists from the Chengdu Institute of Biology and other regional institutions recently identified a new species of pitviper that had been overlooked for decades. The results are published in the open-access journal Zoosystematics and Evolution.

Trimeresurus lii in life. (Image credit: Bo Cai).

Named Trimeresurus lii, or the Huaxi Green Pitviper, the snake was previously confused with the more common bamboo pitviper. Through a combination of genetic sequencing and detailed physical analysis, researchers determined that these populations represent a distinct lineage. The species name honours Li Er, the philosopher known as Laozi, whose teachings emphasise the balance between humanity and the natural world.

Fresh specimen of the holotype of Trimeresurus lii. (Image credit: Bo Cai).

Visually, the Huaxi Green Pitviper is defined by its vibrant grass-green body and distinct eye colors that range from amber to orange-yellow. There are clear physical differences between the sexes. Males feature a tricolor stripe of red and white along their sides, while females possess a simpler yellow stripe. One of the technical features that helped researchers distinguish this snake from its relatives is its smooth head scales, a trait not found in similar species within the region.

Habitat of Trimeresurus lii. (Image credit: Bo Cai).

The discovery took place in the West China Rain Zone, specifically around Mt. Emei and Xiling Snow Mountain. This area is a known biodiversity hotspot, yet many of its smaller or less charismatic species remain understudied. The identification of Trimeresurus lii as the 58th species in its genus serves as a reminder that even well-documented regions still hold biological secrets.

Map showing the type localities of Trimeresurus species and the localities of Trimeresurus lii. (Image credit: Cai et al.).

This find underscores the broader value of the Giant Panda National Park. By protecting large swaths of habitat for flagship species, the park inadvertently preserves a complex ecosystem of specialised reptiles and amphibians. Documenting these animals is a necessary step toward understanding the full scope of life within China’s protected wilderness.

Original source:

Cai B, Gou Y, Wang G, Liu F, Liang D, Gu X, Gu H, Fang H, Liu Y, Li Q, Ding L (2026) A new species of the genus Trimeresurus Lacépède, 1804 (Squamata, Viperidae) from western Sichuan Province, China. Zoosystematics and Evolution 102(1): 285-302. https://doi.org/10.3897/zse.102.178601

Check out the Zoosystematics and Evolution website and follow the journal on BlueSky and Facebook.